It has for some time been standard practice to provide holders for beverage containers, such as cans, glasses or bottles, that can be mounted on the sides or walls of a vessel and are so designed that they will positively hold the can or other container with sufficient certainty that motion of the structure on which the holder is mounted will not cause the container to be released. It has been known to make these devices in a manner such that they have a back panel which is positively secured to a generally vertical wall of the vessel on which they are mounted and a collar device or clamping means which is pivotally mounted to the back panel for movement between a storage position parallel to the back panel and an erected position in which it extends substantially horizontal or at right angles to the back panel. It is also well-known to make the container clamping means pivotal between a storage position parallel to the back panel and an erected position normal to the back panel. It is also known to provide such a support with a cover which is pivotally secured to the lower end of the back panel and in erected position provides a base support for the can, bottle or glass and in storage position seats over the folded clamp member and covers it and the back panel. The problem with these devices has been that they are limited to containers of a single size whereas various types of beverages are merchandised in containers of various sizes. Further, should it be desired to use the device for holding a different type of liquid container, such as a coffee cup, the clamp member having an opening of a fixed size is incapable of use with many cups and similar beverage holders.